JP2010015818A - Electron source device and ion system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electron source or an ion source equipped with an accelerating tube of a simple structure and for smoothing a voltage distribution. <P>SOLUTION: The accelerating tube has a semiconducting material. Therefore, a high-speed tube is so structured that the same current flows in it as that of electron beams emitted from a chip via an anode electrode. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electron source device that generates an electron beam or an ion source device that generates an ion beam.

  In an electron microscope, an electron source that generates an electron beam is used. In an ion beam processing apparatus, a heavy ion accelerator, and the like, an ion source that generates an ion beam is used. An electron source or an ion source accelerates an electron or ion generated by a high voltage toward an anode (in the case of an electron beam or an anion beam) or a cathode (in the case of a positive ion beam). Get the beam. The anode or cathode has a ground potential or a potential close to zero. Accordingly, the electron beam and the ion beam are accelerated by the high potential difference between the electron source and the ion source and the ground potential, respectively.

  For example, in the case of an electron gun used in an electron microscope, the energy of the electron beam is accelerated from several hundred volts to several hundred thousand electron volts. Although the electron beam may be further accelerated by a high-frequency potential after the initial acceleration, in an ordinary electron microscope, the electron beam generated by the electron source is used as it is.

  In addition, in a particle (ion) accelerator called a cockcroft-Walton type or a bandegraph type, a high potential difference is used to give the total energy of ions.

  In an electron source or an ion source, a tube called an “acceleration tube” serving as a passage for an electron beam or an ion beam is provided between both ends of a high potential difference. The inside of the accelerating tube is a vacuum, and often serves as a vacuum vessel. In a typical electron gun, the electron beam extracted from the electron source by the potential difference with the first anode and emitted is converged by the lens action with the second anode and accelerated between the anode. An accelerating tube is provided between the second anode and the anode.

Generally, an acceleration tube is provided with a number of intermediate electrodes. The reason why the intermediate electrode needs to be provided in the acceleration tube is as follows.
1. There is a high potential difference between the second anode and the anode (ground potential). Therefore, a portion where the potential difference changes abruptly appears between them, and electric field concentration occurs there. In this electric field concentration region, dielectric breakdown or field emission may occur. Therefore, if an intermediate electrode is provided, a relatively smooth voltage distribution is generated between the second anode and the anode (ground potential), and such danger is avoided.
2. In order to insulate between the vicinity of the second anode maintained at a high voltage and the ground potential, a tube made of an insulator such as ceramic or acrylic is used as a wall of the vacuum duct. When electrons collide with the tube by reflection or scattering, a local potential distribution is formed. Such potential distribution adversely affects the acceleration potential for accelerating electrons and causes discharge. Therefore, providing an intermediate electrode prevents such electrons from colliding with the tube.
3. Particularly in the case of an electron beam, the electron beam fluctuates with the fluctuation of the external magnetic field. For this reason, the electron gun needs to have a magnetic shield structure. The intermediate electrode is made to act as this magnetic shield.

  For these reasons, it is common to provide an intermediate electrode on an acceleration tube in a high-voltage electron gun, a bandegraph accelerator, or the like.

JP 2001-319613 A (US Pat. No. 7060978) JP 9-17369 A (US Pat. No. 5,677,530) JP 8-264149 A WO 2003/107383 (US Pat. No. 7,193,221)

  By providing the intermediate electrode in the acceleration tube of the electron source or the ion source, it is possible to avoid a region where the potential difference changes abruptly.

  However, in the conventional accelerator tube, in order to obtain a smooth voltage distribution, it is necessary to provide a large number of intermediate electrodes, and the structure becomes complicated. Further, when a large number of intermediate electrodes are provided, the dimension of the electron source or ion source in the axial direction increases. Furthermore, when a large number of intermediate electrodes are provided, it is difficult to accurately align the constituent elements, which may increase aberrations.

  An object of the present invention is to provide an electron source or an ion source including an acceleration tube that has a simple structure and can smooth a voltage distribution.

  The present invention relates to an electron source device that generates an electron beam and an ion device that generates an ion beam. According to the invention, the accelerator tube comprises a semiconductive material. The high-speed tube is configured such that the same current as the current value of the electron beam emitted from the tip via the anode electrode flows.

  ADVANTAGE OF THE INVENTION According to this invention, the electron source or ion source provided with the acceleration tube which has a simple structure and can make voltage distribution smooth can be obtained.

  A first example of an electron gun according to the present invention will be described with reference to FIG. The electron gun of this example includes a chip 11, an extraction electrode 13, a focusing electrode 15, an anode electrode 17, a cylindrical insulator 21, and a cylindrical acceleration tube 23. The extraction electrode 13 has the shape of a cylindrical container having a central hole at the bottom. The focusing electrode 15 has a first cylindrical portion on the tip 11 side and a second cylindrical portion on the anode electrode 17 side. The inner diameter and outer diameter of the first cylindrical portion are larger than the inner diameter and outer diameter of the second cylindrical portion, respectively. As illustrated, a part of the extraction electrode 13 is inserted into the first cylindrical portion of the focusing electrode 15. The anode electrode 17 has the shape of a cylindrical container having a central hole at the bottom. The center hole of the tip 11, the extraction electrode 13, the center axis of the focusing electrode 15, and the center hole of the anode electrode 17 are arranged along the center axis of the electron gun.

  A first electrode terminal 13 a is connected to the extraction electrode 13. A second electrode terminal 15 a is connected to the focusing electrode 15. A third electrode 17 a is connected to the anode electrode 17. The first electrode terminal 13a extends from the extraction electrode 13 to the end of the insulator 21 (upper end in FIG. 1). Furthermore, the tip protrudes outward from the cylindrical outer surface of the insulator 21. The second electrode terminal 15 a extends from the focusing electrode 15 to a connection portion between the insulator 21 and the acceleration tube 23. Furthermore, the tip protrudes outward from the cylindrical outer surfaces of the insulator 21 and the acceleration tube 23. The third electrode 17a extends from the anode electrode 17 to the end of the acceleration tube 23 (the lower end in FIG. 1). Further, the tip protrudes outward from the cylindrical outer surface of the acceleration tube 23.

The insulator 21 and the inside of the acceleration tube 23 are evacuated. Outside of the insulator 21 and the acceleration tube 23, it may be air, such as a resin nonconductor, or may be a gas such as SF _6.

  A first high voltage power supply 41 is connected between the chip 11 and the ground potential. Accordingly, the DC voltage V 0 from the first high-voltage power supply 41 is applied to the chip 11. A second high-voltage power supply 42 is connected between the chip 11 and the first electrode terminal 13a. Accordingly, the DC voltage V <b> 1 from the second high-voltage power supply 42 is applied between the chip 11 and the extraction electrode 13. A third high-voltage power supply 43 is connected between the chip 11 and the second electrode terminal 15a. Accordingly, the DC voltage V <b> 2 from the third high voltage power supply 43 is applied between the tip 11 and the focusing electrode 15. The third electrode 17a is grounded. Therefore, the potential of the anode electrode 17 is equal to the ground potential.

  The potential difference between the focusing electrode 15 and the anode electrode 17 can be obtained by subtracting the potential difference V2 between the tip 11 and the focusing electrode 15 from the potential V0 of the tip 11. Therefore, the potential difference between the focusing electrode 15 and the anode electrode 17 is V0−V2. In the acceleration tube 23, a voltage distribution corresponding to a potential difference V0-V2 (several hundred kilovolts) is generated. The voltage distribution in the acceleration tube 23 will be described with reference to FIG.

  When a voltage is applied to the chip 11 from the high-voltage power supply 41, electrons are emitted from the chip 11 by the principle of field effect or thermionic emission. The emitted electrons are initially accelerated by the extraction electrode 13. The accelerated electrons are accelerated and converged by an electrostatic lens action formed between the extraction electrode 13 and the focusing electrode 15 to become an electron beam. The electron beam further passes through the accelerating tube 23 and is accelerated toward the anode electrode 17 to be given predetermined energy. According to the present invention, preferably, the current value flowing through the acceleration tube 23 is equal to the current value of the electron beam.

  The insulator 21 is an insulator. The insulator 21 electrically insulates between the extraction electrode 13 and the focusing electrode 15. The chip 11 and the extraction electrode 13 are also insulated by an insulator. The acceleration tube 23 is a semiconductor. The acceleration tube 23 is formed of a high resistance semiconductor. Therefore, the focusing electrode 15 and the anode electrode 17 are not completely insulated. A small amount of current flows between the focusing electrode 15 and the anode electrode 17. That is, a current of several microamperes flows through the acceleration tube 23. A DC voltage of several kilovolts to several megavolts is applied to both ends of the acceleration tube 23. Therefore, the resistance value of the acceleration tube 23 is several gigaΩ.

  A method for manufacturing the acceleration tube 23 will be described. The insulator 21 is an insulator, while the acceleration tube 23 is a semiconductor. The acceleration tube 23 may be manufactured by forming a cylindrical member from a semiconductive material. However, the accelerating tube 23 may be manufactured by forming a cylindrical member from an insulating material and forming a film or layer of a semiconductive material on the inner surface thereof. Various materials are known as semiconductive materials. For example, there are conductive ceramics.

  The insulator 21 and the accelerating tube 23 may be manufactured as separate members, and both may be joined, but both may be manufactured as an integral cylindrical member. For example, a cylindrical member is formed of an insulating material, and a film or layer of a semiconductive material is formed only on a part thereof. The portion where the semiconductive material is applied becomes the acceleration tube 23, and the portion where the semiconductive material is not applied becomes the insulator 21.

  A comparative example of an electron gun will be described with reference to FIG. The electron gun of this example includes a chip 11, a lead electrode 13, a focusing electrode 15, an anode electrode 17, first to third intermediate electrodes 19A, 19B, and 19C, and first to fifth insulators 21A to 21E. . The shapes of the chip 11, the extraction electrode 13, the focusing electrode 15, and the anode electrode 17 may be the same as those in the first example shown in FIG. The first to fifth insulators 21A to 21E may be the same as the insulator 21 of the first example shown in FIG.

  The intermediate electrodes 19A, 19B, and 19C each have a first cylindrical portion on the tip 11 side and a second cylindrical portion on the anode electrode 17 side. The inner diameter and outer diameter of the first cylindrical portion of the intermediate electrodes 19A, 19B, and 19C are larger than the inner diameter and outer diameter of the second cylindrical portion, respectively. As illustrated, a part of the extraction electrode 13 is inserted into the first cylindrical portion of the focusing electrode 15. A part of the second cylindrical portion of the focusing electrode 15 is inserted into the first cylindrical portion of the first intermediate electrode 19A. A part of the second cylindrical portion of the first intermediate electrode 19A is inserted into the first cylindrical portion of the second intermediate electrode 19B. A part of the second cylindrical portion of the second intermediate electrode 19B is inserted into the first cylindrical portion of the third intermediate electrode 19C. A part of the second cylindrical portion of the third intermediate electrode 19 </ b> C is inserted into the anode electrode 17.

  A first electrode terminal 13 a is connected to the extraction electrode 13, a second electrode terminal 15 a is connected to the focusing electrode 15, and a sixth electrode terminal 17 a is connected to the anode electrode 17. The third to fifth electrode terminals 19a, 19b, and 19c are connected to the intermediate electrodes 19A, 19B, and 19C, respectively. The sixth electrode 17a is grounded.

  A first resistor 44 is connected between the second electrode terminal 15a and the third electrode terminal 19a, and a second resistor 45 is connected between the third electrode terminal 19a and the fourth electrode terminal 19b, A third resistor 46 is connected between the fourth electrode terminal 19b and the fifth electrode terminal 19c, and a fourth resistor 47 is connected between the fifth electrode terminal 19c and the sixth electrode terminal 17a. Yes.

  A first high voltage power supply 41 is connected between the chip 11 and the ground potential, a second high voltage power supply 42 is connected between the chip 11 and the first electrode terminal 13a, and the chip 11 and the third electrode terminal 15a are connected. A third high-voltage power supply 43 is connected between them. Accordingly, the DC voltage V0 from the first high-voltage power supply 41 is applied to the chip 11 as in the case of the first example of FIG. A DC voltage V <b> 1 from the second high voltage power supply 42 is applied between the chip 11 and the extraction electrode 13. A DC voltage V <b> 2 from the third high voltage power supply 43 is applied between the chip 11 and the focusing electrode 15. The potential difference between the focusing electrode 15 and the anode electrode 17 is V0−V2.

  A voltage distribution corresponding to a potential difference V0−V2 (several hundred kilovolts) is generated between the focusing electrode 15 and the anode electrode 17. The voltage distribution in the focusing electrode 15, the intermediate electrodes 19A to 19C, and the anode electrode 17 will be described with reference to FIG. The current value flowing through the high voltage power supply 43 and the resistors 44 to 47 is equal to the current value of the electron beam.

  FIG. 3 shows potential distributions in the first example of the electron gun of the present invention shown in FIG. 1 and the comparative example of the electron gun shown in FIG. As shown, a position coordinate axis x is taken in the direction of the central axis of the electron gun, and a potential coordinate axis V is taken perpendicularly thereto. In the first example of the electron gun of the present invention shown in FIG. 1, the anode electrode 17 is grounded, and its potential is equal to the ground potential. The potential of the chip 11 with respect to the ground potential is set to V0. The potential difference between the tip 11 and the anode electrode 17 is also V0. The potential difference between the chip 11 and the extraction electrode 13 is V1. The potential of the extraction electrode 13 with respect to the ground potential is V0-V1. The potential difference between the extraction electrode 13 and the anode electrode 17 is also V0−V1. The potential difference between the tip 11 and the focusing electrode 15 is V2. The potential of the focusing electrode 15 with respect to the ground potential is V0-V2. The potential difference between the focusing electrode 15 and the anode electrode 17 is also V0−V2 (several hundred kilovolts).

  Therefore, voltages V0-V2 are applied to both ends of the acceleration tube 23. Let R be the resistance of the acceleration tube 23. If the current flowing through the acceleration tube 23 is I, then I = (V0−V2) / R. The value of this current I is several microamperes. The current value flowing through the acceleration tube 23 is preferably equal to the current value of the electron beam.

  As described above, when a minute current flows through the acceleration tube 23, the potential inside the acceleration tube 23 is smoothly distributed. A potential distribution that is approximately proportional to the distance is generated between the focusing electrode 15 and the anode electrode 17. An electron beam flies in such an electric field. Therefore, the electron beam from the focusing electrode 15 to the anode electrode 17 is accelerated with little aberration. Note that some of the electrons that have collided with the anode electrode 17 reach the inside of the acceleration tube 23 as reflected electrons (or secondary electrons), but since the total amount thereof is less than the current flowing through the acceleration tube 23, the acceleration tube 23 potential gradient is not affected.

  In the comparative electron gun shown in FIG. 2, the anode electrode 17 is grounded, and its potential is equal to the ground potential. The potential of the chip 11 with respect to the ground potential is set to V0. The potential difference between the tip 11 and the anode electrode 17 is also V0. The potential difference between the chip 11 and the extraction electrode 13 is V1. The potential of the extraction electrode 13 with respect to the ground potential is V0-V1. The potential difference between the extraction electrode 13 and the anode electrode 17 is also V0−V1. The potential difference between the tip 11 and the focusing electrode 15 is V2. The potential of the focusing electrode 15 with respect to the ground potential is V0-V2. The potential difference between the focusing electrode 15 and the anode electrode 17 is also V0−V2. That is, the potential distribution from the tip 11 to the focusing electrode 15 is the same as that of the electron gun of the present invention shown in FIG.

  However, the potential distribution between the focusing electrode 15 and the anode electrode 17 is different from that of the electron gun of the present invention shown in FIG.

  As shown in FIG. 2, resistors 44 to 47 are connected in parallel to the second to fifth insulators 21B to 21E, respectively. Further, four resistors 44 to 47 are connected in series with the third high-voltage power supply 43. The current flowing through the third high-voltage power supply 43 is I. The current value flowing through the third high-voltage power supply 43 is assumed to be equal to the current value of the electron beam. The potential difference between the focusing electrode 15 and the first intermediate electrode 19A is I × R1, the potential difference between the first intermediate electrode 19A and the second intermediate electrode 19B is I × R2, and the second intermediate electrode 19B and the third intermediate electrode 19B. The potential difference between the intermediate electrodes 19C is I × R3, and the potential difference between the third intermediate electrode 19C and the anode electrode 17 is I × R4.

  By making the resistance values of the four resistors 44 to 47 the same, the potential difference V0-V2 between the focusing electrode 15 and the anode electrode 17 can be divided into four equal parts. In this case, the potentials of the focusing electrode 15, the first intermediate electrode 19A, the second intermediate electrode 19B, the third intermediate electrode 19C, and the anode electrode 17 are (V0-V2), 3/4 (V0), respectively. -V2), 1/2 (V0-V2), 1/4 (V0-V2), 0 (ground potential). Therefore, the voltage distribution between the focusing electrode 15 and the anode electrode 17 is a polygonal line, but is distributed smoothly.

  Incidentally, a part of the electrons colliding with the anode electrode 17 returns into the intermediate electrode as reflected electrons (or secondary electrons). However, in the example of FIG. 2, the intermediate electrodes 19 </ b> A to 19 </ b> C have shapes that overlap each other. Therefore, the reflected electrons do not reach the insulator beyond the intermediate electrode. If the reflected electrons reach the insulator, they remain and accumulate there. Such electrons affect the voltage distribution between the focusing electrode 15 and the anode electrode 17. However, as shown in FIG. 2, by arranging the intermediate electrodes 19A to 19C so as to overlap each other, the reflected electrons are prevented from reaching the insulator.

  The first example of the electron gun according to the present invention in FIG. 1 is compared with the comparative example of the electron gun in FIG. In the electron gun of FIG. 1, the potential distribution between the focusing electrode 15 and the anode electrode 17 can be made smooth by using the accelerating tube as a semiconductor. On the other hand, the electron gun of FIG. 2 uses an insulating insulator for the accelerating tube, but smoothes the potential distribution between the focusing electrode 15 and the anode electrode 17 by using an intermediate electrode. Therefore, in the electron gun of FIG. 1, the intermediate electrodes and resistors necessary for the electron gun of FIG. 2 can be reduced or eliminated. Therefore, in the electron gun of the present invention, the number of parts is reduced, so that the manufacturing cost can be reduced. In addition, since the structure of the electron gun of the present invention is simple, it is easy to manufacture and adjust. In the electron gun of the present invention, in particular, the device for arranging the focusing electrode 15, the anode electrode 17 and the intermediate electrode on the same axis and the device for holding can be simplified or unnecessary. The total length of the electron gun according to the present invention can be shorter than the total length of the comparative example. Therefore, the electron gun of the present invention can be easily cleaned. Therefore, in the electron gun of the present invention, the conductance of evacuation by a vacuum pump is improved. For the above two reasons, the degree of vacuum inside the accelerating tube can be improved in the electron gun of the present invention. In addition, since the electron gun of the present invention can be shortened in overall length, the performance is less likely to change even with environmental fluctuations such as temperature fluctuations and external magnetic field fluctuations.

  A second example of an electron gun according to the present invention will be described with reference to FIG. The electron gun of this example includes a chip 11, an extraction electrode 13, a focusing electrode 15, an anode electrode 17, a cylindrical insulator 22, and a cylindrical acceleration tube 23. The shapes of the chip 11, the extraction electrode 13, the focusing electrode 15, and the anode electrode 17 may be the same as those in the first example shown in FIG.

  The acceleration tube 23 of this example may be made of the same structure and the same material as the acceleration tube used in the first example shown in FIG. In this example, the acceleration tube extends from the extraction electrode 13 to the anode electrode 17. The insulator 22 extends from the extraction electrode 13 to the focusing electrode 15. The insulator 22 is disposed inside the acceleration tube 23.

  A first electrode terminal 13 a is connected to the extraction electrode 13. A second electrode terminal 15 a is connected to the focusing electrode 15. A third electrode 17 a is connected to the anode electrode 17. The first electrode terminal 13a extends from the extraction electrode 13 to the ends of the insulator 21 and the acceleration tube 23 (upper end in FIG. 4). The tip protrudes outward from the cylindrical outer surface of the acceleration tube 23. The second electrode terminal 15a extends from the focusing electrode 15 to the end of the insulator 21 (the lower end in FIG. 4). The tip extends to the cylindrical outer surface of the insulator 21, but does not protrude outward. The third electrode terminal 17a extends from the extraction electrode 13 to the end of the acceleration tube 23 (lower end in FIG. 4). The tip protrudes outward from the cylindrical outer surface of the acceleration tube 23.

  In the electron gun of this example, the potential difference V0 between the tip 11 and the anode electrode 17 is smoothly distributed. That is, the potential distribution from the tip 11 to the focusing electrode 15 changes smoothly and does not become a polygonal line.

  In the electron gun of this example, the dimension in the axial direction of the electron gun can be shortened only in the insulator portion as compared with the first example shown in FIG. Therefore, the tip 11, the extraction electrode 13, the focusing electrode 15, and the anode electrode 17 can be easily arranged along the central axis of the electron gun. That is, it is easy to obtain coaxiality and maintain it.

  Further, the structure of the electron gun can be simplified compared to the case of the first example. Therefore, the electron gun of this example can be reduced in price and increased in accuracy.

  1 and 4, the example of the electron gun according to the present invention has been described. However, the present invention is not limited to an electron source device such as an electron gun, and includes an ion source device that generates an ion beam. The ion source device according to the present invention basically has the same structure as the electron gun shown in FIGS. In the case of an ion source device, when an anion beam is generated, an anode electrode is used as in the case of an electron gun. However, when a cation beam is generated, a cathode electrode is used instead of the anode electrode.

  The example of the present invention has been described above, but the present invention is not limited to the above-described example, and various modifications can be easily made by those skilled in the art within the scope of the invention described in the claims. Will be understood.

It is a figure which shows the structure of the 1st example of the electron gun by this invention. It is a figure which shows the structure of the comparative example of an electron gun. It is a figure which shows the example of the voltage distribution of the 1st example of the electron gun by this invention of FIG. 1, and the comparative example of FIG. It is a figure which shows the structure of the 2nd example of the electron gun by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Tip, 13 ... Extraction electrode, 15 ... Focusing electrode, 17 ... Anode electrode, 19A, 19B, 19C ... Intermediate electrode, 21, 21A-21E, 22 ... Insulator, 23 ... Accelerating tube, 13a, 15a, 17a ... Electrode Terminal

Claims (18)

A chip that emits electrons, an extraction electrode that is electrically insulated from the chip in order to extract electrons from the chip, a focusing electrode for focusing electrons from the extraction electrode, and the extraction electrode A cylindrical insulator provided between the focusing electrodes; an anode electrode electrically insulated from the focusing electrode for drawing electrons from the focusing electrode; and a vacuum vessel for holding the interior in a vacuum A first high-voltage power supply that applies a first DC voltage V0 between the chip and the ground potential; a second high-voltage power supply that applies a second DC voltage V1 between the chip and the extraction electrode; An electron source device comprising: a third high-voltage power source that applies a third DC voltage V1 between the tip and the focusing electrode;
The vacuum vessel has a cylindrical high-speed tube, one end of the high-speed tube is connected to the anode electrode, and the other end of the high-speed tube is connected to the focusing electrode or the extraction electrode. The electron source device is configured so that the same current as the current value of the electron beam emitted from the chip via the anode electrode flows.   2. The electron source device according to claim 1, wherein the high-speed tube is made of a semiconductor material.   2. The electron source device according to claim 1, wherein the high-speed tube is made of conductive ceramics.   2. The electron source device according to claim 1, wherein the high-speed tube is formed by forming a film or layer of a semiconductor material on an inner surface of a cylindrical member made of an insulating material. apparatus.   2. The electron source device according to claim 1, wherein a resistance value of the acceleration tube is several giga ohms.   2. The electron source apparatus according to claim 1, wherein when a DC voltage of several kilovolts to several megavolts is applied to both ends of the acceleration tube, a current of several microamperes flows through the acceleration tube. .   2. The electron source device according to claim 1, wherein the high-speed tube is disposed between the anode electrode and the focusing electrode, the insulator is disposed between the extraction electrode and the focusing electrode, and the acceleration tube and the insulator are An electron source device characterized by being connected in series.   7. The electron source device according to claim 6, wherein the acceleration tube and the insulator have an integral structure.   9. The electron source device according to claim 8, wherein the accelerating tube and the insulator are formed by a single cylinder formed of an insulating material, and a semiconductor material is formed on a portion constituting the accelerating tube inside the cylinder. An electron source device characterized in that a film or a layer is formed.   2. The electron source apparatus according to claim 1, wherein the high-speed tube is disposed between the anode electrode and the extraction electrode, the insulator is disposed between the extraction electrode and the focusing electrode, and the insulator is disposed on the acceleration tube. An electron source device arranged on the inner side. A chip that emits an ion beam; an extraction electrode that is electrically insulated from the chip to extract ions from the chip; a focusing electrode that focuses ions from the extraction electrode; and the extraction electrode And a cylindrical insulator provided between the focusing electrode, an anode or a cathode electrically insulated from the focusing electrode to attract ions from the focusing electrode, and a vacuum for keeping the inside in a vacuum A container, a first high-voltage power supply that applies a first DC voltage V0 between the chip and the ground potential, and a second high-voltage power supply that applies a second DC voltage V1 between the chip and the extraction electrode And a third high-voltage power source that applies a third DC voltage V1 between the tip and the focusing electrode,
The vacuum vessel has a cylindrical high-speed tube, one end of the high-speed tube is connected to the anode or cathode, and the other end of the high-speed tube is connected to the focusing electrode or the extraction electrode. Is configured such that the same current as the current value of the ion beam emitted from the chip via the anode or cathode flows.   12. The ion source apparatus according to claim 11, wherein the high-speed tube is made of a semiconductor material.   12. The ion source device according to claim 11, wherein the high-speed tube is made of conductive ceramics.   12. The ion source device according to claim 11, wherein the high-speed tube is formed by forming a film or a layer of a semiconductor material on an inner surface of a cylindrical member formed of an insulating material. apparatus.   12. The ion source device according to claim 11, wherein the acceleration tube and the insulator have an integral structure.   12. The ion source device according to claim 11, wherein the acceleration tube and the insulator are formed by a single cylinder formed of an insulating material, and a semiconductor material is formed inside the cylinder at a portion constituting the acceleration tube. An ion source device characterized in that a film or a layer is formed. A chip that emits electrons, an extraction electrode that is electrically insulated from the chip to extract electrons from the chip, a focusing electrode that focuses electrons from the extraction electrode, and the focusing electrode A method of generating an electron beam using an electron source device having an anode electrode for drawing in electrons and a vacuum vessel having a cylindrical high-speed tube and holding the inside in a vacuum,
Applying a first DC voltage V0 between the chip and ground potential;
Applying a second DC voltage V1 between the chip and the extraction electrode;
Applying a third DC voltage V1 between the tip and the focusing electrode;
Connecting one end of the high-speed tube to the anode electrode and connecting the other end of the high-speed tube to the focusing electrode or the extraction electrode;
Flowing the same current as the current value of the electron beam emitted from the tip via the anode electrode to the high-speed tube;
A method for generating an electron beam comprising:   18. The electron beam generating method according to claim 17, wherein when a DC voltage of several kilovolts to several megavolts is applied to both ends of the acceleration tube, a current of several microamperes flows through the acceleration tube. Line generation method.

Images